SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '30b881b146c583ad9f6a46245c7112977e3fcf64940ea018b61734019818d8dc' 
  AND token = 'opRDPZdQ6hNlpnJWzC0Lm99k2f9O7ftZ0HZF7nKC22k=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}